Phpunit test not running with multiple database setup

We have a multi-tenancy set up with one main and other tenant databases and having some problems running non-sqlite tests. Databases are mysql.

Currently trying to run tests against the main database and one tenant database. The connections in my model constructors are set like so:

BaseMainModel

$this->connection = config('database.main');

BaseTenantModel

$this->connection = config('database.tenant');

I observe the following:

Test are running fine with an sqlite in memory databse with the following settings in phpunit.xml:

    <env name="APP_ENV" value="testing"/>
    <env name="CACHE_DRIVER" value="array"/>
    <env name="SESSION_DRIVER" value="array"/>
    <env name="QUEUE_DRIVER" value="sync"/>
    <env name="APP_DEBUG" value="true"/>
    <env name="DB_CONNECTION" value="testing"/>
    <env name="DB_CONNECTION_TENANT" value="testing"/>

In config.database.connections

        'testing' => [
            'driver' => 'sqlite',
            'database' => ':memory:',
            'prefix' => '',
        ],

However, when running without the sqlite in memory database (so commenting out my two phpunit lines for <env name="DB_CONNECTION" value="testing"/> and <env name="DB_CONNECTION_TENANT" value="testing"/>) and running on my normal database, the tests start hanging after the first test.

So for example, if I have 5 tests in a file SomeTests.php, the first one completes, and the process hangs on the second one.

If I add the protected $connectionsToTransact = ['main', 'tenant']; to my TestCase class, even the first test doesn't complete.

Another thing to note is that I am overriding the refreshTestDatabase() method of the RefreshDatabase trait by creating my own trait and using laravel's trait. My trait looks like so:

trait RefreshDatabase
{
    use BaseRefreshDatabase;

    /**
     * Refresh the in-memory database.
     *
     * @return void
     */
    protected function refreshInMemoryDatabase()
    {
        $this->artisan('migrate');

        $path = 'database' . DIRECTORY_SEPARATOR . 'migrations' . DIRECTORY_SEPARATOR . 'tenants';

        Artisan::call('migrate', [
            '--database' => 'testing',
            '--path' => $path
        ]);

        $this->app[Kernel::class]->setArtisan(null);
    }

    /**
     * Refresh a conventional test database.
     *
     * @return void
     */
    protected function refreshTestDatabase()
    {
        if (!RefreshDatabaseState::$migrated) {

            $this->artisan('migrate:fresh');

            $path = 'database' . DIRECTORY_SEPARATOR . 'migrations' . DIRECTORY_SEPARATOR . 'tenants';

            $this->artisan('migrate:fresh', [
                '--path' => $path,
                '--database' => config('database.tenant')
            ]);

            $this->app[Kernel::class]->setArtisan(null);

            RefreshDatabaseState::$migrated = true;
        }

        $this->beginDatabaseTransaction();
    }
}

I tried dumping in my test's setUp function:

class RelationsTest extends TestCase
{
    use RefreshDatabase;

    protected function setUp()
    {
        parent::setUp();
        dump("here");  // this is logged
        $this->product = factory(Product::class)->create();
        dump("product created"); // this is not. However I dumped in the model constructors and it did enter the Product constructor
        $this->someClass= factory(SomeClass::class)->create();
        $this->user = factory(User::class)->create();
        $this->otherClass = factory(OtherClass::class)->create();

        $this->yetAnotherClass= factory(YetAnotherClass::class)->create([
            'owner_id' => $this->user->id,
            'product_id' => $this->product->id,
            'someClass_id' => $this->someClass->id,
        ]);
    }
...

Interestingly, if I run every test in the file separately, they run fine. So something happens in between the tests that I don't understand!

If I run two basic tests with just assertTrue(true) (not using factories or touching the database), they run fine.

Help is much appreciated! Thanks :)